Condensed Consolidated Statements of Changes in Equity (USD $) In Millions, except Share data	Total	Common Stock [Member]	Additional Paid In Capital [Member]	Retained Earnings [Member]	Foreign Currency Translation Adjustments [Member]	Net Gains (Losses) on Cash Flow Hedges [Member]	Net Gains (Losses) on Available for Sale Securities [Member]	Pension and OPEB Related Adjustments [Member]	Common Stockholders' Equity [Member]	Noncontrolling Interest [Member]	Duke Energy Carolinas [Member]	Duke Energy Carolinas [Member] Members Equity [Member]	Duke Energy Carolinas [Member] Net Gains (Losses) on Cash Flow Hedges [Member]	Duke Energy Carolinas [Member] Net Gains (Losses) on Available for Sale Securities [Member]	Progress Energy [Member]	Progress Energy [Member] Additional Paid In Capital [Member]	Progress Energy [Member] Retained Earnings [Member]	Progress Energy [Member] Net Gains (Losses) on Cash Flow Hedges [Member]	Progress Energy [Member] Net Gains (Losses) on Available for Sale Securities [Member]	Progress Energy [Member] Pension and OPEB Related Adjustments [Member]	Progress Energy [Member] Common Stockholders' Equity [Member]	Progress Energy [Member] Noncontrolling Interest [Member]	Duke Energy Progress [Member]	Duke Energy Progress [Member] Common Stock [Member]	Duke Energy Progress [Member] Retained Earnings [Member]	Duke Energy Florida [Member]	Duke Energy Florida [Member] Common Stock [Member]	Duke Energy Florida [Member] Retained Earnings [Member]	Duke Energy Florida [Member] Net Gains (Losses) on Cash Flow Hedges [Member]	Duke Energy Ohio [Member]	Duke Energy Ohio [Member] Common Stock [Member]	Duke Energy Ohio [Member] Additional Paid In Capital [Member]	Duke Energy Ohio [Member] Retained Earnings [Member]	Duke Energy Indiana [Member]	Duke Energy Indiana [Member] Common Stock [Member]	Duke Energy Indiana [Member] Additional Paid In Capital [Member]	Duke Energy Indiana [Member] Retained Earnings [Member]	Duke Energy Indiana [Member] Net Gains (Losses) on Cash Flow Hedges [Member]
Beginning member's equity at Dec. 31, 2013											$ 10,350	$ 10,365	$ (14)	$ (1)
Balance at Dec. 31, 2013	41,408	1	39,365	2,363	(307)	(40)		(52)	41,330	78					10,864	7,467	3,452	(43)		(16)	10,860	4	5,625	2,159	3,466	4,797	1,762	3,036	(1)	5,269	762	4,882	(375)	3,939	1	1,384	2,551	3
Balance, in shares at Dec. 31, 2013		706,000,000
Net income (loss)	(93)			(97)					(97)	4					203		202				202	1
Net Income (Loss) Attributable to Parent	(97)										286	286			202								133		133	108		108		(890)			(890)	113			113
Other comprehensive income (loss), net of tax	23				23			(1)	22	1	1		1		2			1		1	2					1			1					1				1
Distributions to parent											(126)	(126)
Common stock issuances, including dividend reinvestment and employee benefits	7		7						7
Common stock issuances, including dividend reinvestment and employee benefits, shares		1,000,000
Common stock dividends	(553)			(553)					(553)																	(124)		(124)		(100)		(100)
Distributions to noncontrolling interest in subsidiaries	(3)									(3)					(3)							(3)
Transfer of service company net assets to Duke Energy															(539)		(542)	3			(539)
Ending member's equity at Mar. 31, 2014											10,511	10,525	(13)	(1)
Balance at Mar. 31, 2014	40,789	1	39,372	1,713	(284)	(40)		(53)	40,709	80					10,527	7,467	3,112	(39)		(15)	10,525	2	5,758	2,159	3,599	4,782	1,762	3,020		4,279	762	4,782	(1,265)	4,053	1	1,384	2,664	4
Balance, in shares at Mar. 31, 2014		707,000,000
Beginning member's equity at Dec. 31, 2014											10,924	10,937	(12)	(1)
Balance at Dec. 31, 2014	40,899	1	39,405	2,012	(439)	(59)	3	(48)	40,875	24					11,176	7,467	3,782	(35)	1	(7)	11,208	(32)	5,867	2,159	3,708	5,222	1,762	3,460		4,674	762	4,782	(870)	3,848	1	1,384	2,460	3
Balance, in shares at Dec. 31, 2014	707,000,000	707,000,000													100								160,000,000			100				89,663,086				53,913,701
Net income (loss)	867			864					864	3					263		260				260	3
Net Income (Loss) Attributable to Parent	864										292	292			260								183		183	113		113		149			149	108			108
Other comprehensive income (loss), net of tax	(133)				(121)	(3)		(5)	(129)	(4)					(1)			(2)		1	(1)													(1)				(1)
Common stock issuances, including dividend reinvestment and employee benefits	8		8						8
Common stock issuances, including dividend reinvestment and employee benefits, shares		1,000,000
Common stock dividends	(564)			(564)					(564)																	(350)		(350)
Other	10			(3)					(3)	13							(3)				(3)	3
Ending member's equity at Mar. 31, 2015											11,216	11,229	(12)	(1)
Balance at Mar. 31, 2015	$ 41,087	$ 1	$ 39,413	$ 2,309	$ (560)	$ (62)	$ 3	$ (53)	$ 41,051	$ 36					$ 11,438	$ 7,467	$ 4,039	$ (37)	$ 1	$ (6)	$ 11,464	$ (26)	$ 6,050	$ 2,159	$ 3,891	$ 4,985	$ 1,762	$ 3,223		$ 4,823	$ 762	$ 4,782	$ (721)	$ 3,955	$ 1	$ 1,384	$ 2,568	$ 2
Balance, in shares at Mar. 31, 2015	708,000,000	708,000,000													100								160,000,000			100				89,663,086				53,913,701